Automated methods and systems for analyzing data associated with an industrial process

ABSTRACT

Automated methods and systems for analyzing data associated with an industrial process parse data entries received from devices in an industrial process, such as a mail or paper processing system. The parsing can include applying state machines to the data to identify events and produce output relating to the process for which the data is being analyzed. Statistical measures are computed for the output from each of the state machines. The statistical measures are compared to design limits. Output is displayed to the user in a format that facilitates interpretation of the data.

TECHNICAL FIELD

[0001] The present invention relates to methods and systems foranalyzing data relating to events occurring in industrial processes.More particularly, the present invention relates to automated methodsand systems for analyzing time-tagged data associated with eventsoccurring in industrial processes.

BACKGROUND ART

[0002] Time-tagged data may be used to record events that occur inindustrial processes. For example, in paper or sheet article processing,such as mail processing, machines such as, for example, inserters,turnover sequencers, accumulators, folders, and collectors includeoptical sensors that monitor the flow of sheet articles through themachines. The sheet articles can also include individual or stacked,folded or unfolded sheet articles such as envelopes, envelope insertsand other suitable sheet articles.

[0003] Each sheet article processing machine can comprise a processor, amemory buffer, and a communications circuit, all of which can cooperateto produce time-tagged data for a machine. The optical sensors can beused to detect events, such as the presence of a sheet of paper. Theprocessing circuit receives the data from each of the sensors andassociates a time value with the output of each sensor. The processingcircuit can also convert the output into a code or text stringindicative of the event detected by each sensor. The combination of atime value and a code or text string indicative of an event thatoccurred in an industrial process is referred to herein as “time-taggeddata”. The communication circuits of each of the machines transmit thetime-tagged data to a central location for storage.

[0004] The central location can be a suitable computer that communicateswith each of the machines, e.g., using a serial interface, to receivethe time-tagged data from the machines. The time-tagged data can bestored as a log file in a bulk storage medium, such as a hard disk, atthe central location. Each line of data in the log file is referred toas an entry. Each entry contains one unit of time-tagged data, i.e., onetime tag and one event portion. The entries in the log file are analyzedmanually by a technician or an engineer to identify problems associatedwith the industrial process.

[0005] One problem with this method of recording and analyzing dataregarding an industrial process is that time-tagged data is difficult tointerpret. For example, because time-tagged data is output from multiplesensors on multiple machines or multiple parts of the same machine, andbecause many events can occur simultaneously, no clear sequence oftime-tagged data relating to a single event appears in the log file.Entries recorded by a single sensor can be interspersed with otherentries in the log file. In addition, the text or codes associated witheach event might not readily convey to the observer the nature of theevent. As a result, skilled technicians or even engineers can berequired to analyze the time-tagged data. Because of the complex natureof the time-tagged data, extra labor can be required even for skilledpersons to interpret the time-tagged data.

[0006] The following lines of text are an example of time-tagged datarecorded in a log file for a paper processing operation:

0000.013977 00.465718 ??.?????? BIN_MUX_IN CLR-board=0,port=06, pin=000

0000.014343 00.465718 ??.?????? BIN_MUX_IN CLR-board=0,port=06,pin=000

0000.027557 00.465718 ??.?????? BIN_MUX_IN SET-board=0,port=05, pin=000

0000.031738 00.465718 ??.?????? BIN_MUX_IN CLR-board=0,port=06, pin=000

0000.033447 00.465718 ??.?????? HTA Variable-WRITE: I#3219,val=65535/Oxffff

0000.033569 00.465718 ??.?????? HTA Page Data-INSIDE:s#=16,p#=2,tg=73,ct=1

0000.033661 00.000091 00.000091 FED_EOS-HTA Page Data:1ST_SUBSETFOLD_LIMIT

0000.061371 00.465718 ??.?????? BIN_MUX_IN SET-board=0,port=09,pin=000

0000.061798 00.465718 ??.?????? BIN_MUX_IN SET-board=0,port=09,pin=000

0000.062683 00.465718 ??.?????? HTA Vadable-WRITE: I#2419, val=8/0x0008

[0007] In each log file entry, the numbers on the left side indicate theevent occurrence time in milliseconds measured from a predeterminedstart time.

[0008] The text on the right side of each entry indicates the type ofevent, the name of the sensor that detected the event, and variablevalues associated with the event. As can be seen from the data above, itcan be difficult to determine a real-world event from the event portionof each entry. The difficulty is increased when an event of interestspans multiple separated time-tagged data entries.

[0009] In light of these difficulties, there exists a long-felt need forimproved methods and systems for analyzing time-tagged data, identifyingevents in an industrial process based on the time-tagged data, andpresenting the data in a format that is easily understood.

DISCLOSURE OF THE INVENTION

[0010] The present invention includes automated methods and systems foranalyzing time-tagged data. The phrase “time-tagged data”, as usedherein, refers to any data associated with an industrial process thathas a time value or time-tag indicating when an event occurred and thathas an event portion that indicates the nature of an event. The methodsand systems according to the present invention analyze the time-taggeddata by applying computer-implemented state machines to time-tagged dataentries to produce data indicative of real-world events that occur in anindustrial process. Statistical measures are computed for the dataoutput from the state machines, and the statistical measures arecompared to design limits. The statistical measures and the results ofcomparing the statistical measures to the design limits are presented toa user in a format that facilitates interpretation of the time-taggeddata.

[0011] According to another aspect, the present invention includesmethods and systems for analyzing non-time-tagged data associated withan industrial process and presenting output in a manner that facilitatesunderstanding of the data.

[0012] Accordingly, it is an object of the present invention to providenovel automated methods and systems for analyzing time-tagged data.

[0013] It is another object of the invention to provide methods andsystems for analyzing time-tagged data to produce output thatfacilitates interpretation of the time-tagged data.

[0014] It is another object of the invention to provide methods andsystems for analyzing non-time-tagged data associated with an industrialprocess.

[0015] These objects and others are met in whole or in part by thepresent invention. Some of the objects of the invention having beenstated hereinabove, other objects will become evident as the descriptionproceeds, when taken in connection with the accompanying drawings, asbest described hereinbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] A description of the present invention will now proceed withreference to the accompanying drawings of which:

[0017]FIG. 1 is a flow chart illustrating exemplary steps that can beperformed by an automated system for analyzing time-tagged dataaccording to an embodiment of the present invention;

[0018]FIG. 2 is a flow chart illustrating a parser for parsingtime-tagged data according to an embodiment of the present invention;

[0019]FIG. 3 is a state diagram of a state machine for identifyingstarting and ending events associated with an industrial processaccording to an embodiment of the present invention;

[0020]FIG. 4 is a state diagram of a state machine for identifying anoverlapped page event in paper processing according to an embodiment ofthe present invention;

[0021]FIG. 5 is a process flow diagram of a paper processing system inwhich embodiments of the present invention can be used to analyzetime-tagged data;

[0022]FIG. 6(a) is a computer-generated image illustrating an outputwindow for displaying results of analyzing time-tagged data to a useraccording to an embodiment of the present invention;

[0023]FIG. 6(b) is a computer-generated image illustrating a dimensionsdialog box for receiving paper dimensions from a user according to anembodiment of the present invention;

[0024]FIG. 6(c) is a computer-generated image illustrating a processinformation dialog box for receiving process information from a useraccording to an embodiment of the present invention; and

[0025]FIG. 6(d) is a computer-generated image of a report indicatingresults of analyzing time-tagged data according to an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

[0026] In accordance with the present invention, novel automated methodsand systems for analyzing time-tagged data and non-time-tagged data areprovided. The automated methods and systems for analyzing time-taggeddata and non-time-tagged data according to the present invention will beexplained in the context of flow charts and state diagrams. It isunderstood according to this invention that the flow charts and thestate diagrams can be implemented in hardware, software, or acombination of hardware and software. Thus, the present invention caninclude computer program products comprising computer-executableinstructions embodied in computer-readable media for performing thesteps illustrated in each of the flow charts or implementing the statemachines illustrated in each of the state diagrams.

[0027]FIG. 1 is a flow chart illustrating steps that can be performed byan automated system for analyzing time-tagged data according to anembodiment of the present invention. In step ST1, the system parsestime-tagged data to identify events and measure parameters of interest.In step ST2, the system computes statistical measures, such as meanvalues, minimum values, maximum values, standard deviations, modes,medians, and variances, of parameters measured during the parsing of thetime-tagged data. In step ST3, the system applies limits to thestatistical measures data. The limits can be used to identify whetherthe machine or machines is or are operating within acceptable designtolerances. Limits can vary by type and value for each measuredparameter. In step ST4, the system presents or displays output to auser. The output can include the statistical measures and the results ofcomparing statistical measures to the design limits. If the statisticalmeasures fall outside of the design limits, the user can be alertedthrough any suitable means, such as through display of an alert messageon a computer display device. The system may also warn the user if themeasures are close to but do not exceed a design limit. Warning the userwhen operating conditions are close to but not in excess of designlimits allows the user to identify a problem before a failure occurs.Each of the steps illustrated in FIG. 1 will now be discussed in furtherdetail.

[0028]FIG. 2 illustrates an exemplary parser for parsing time-taggeddata according to an embodiment of the present invention. In step ST1,the parser reads one entry of the time-tagged data. For example, theparser can access a log file containing the time-tagged data and readthe first entry from the log file. The parser can execute on the samecomputer or on a different computer than the computer that stores thelog file. If the parser executes on the same computer, the parser canaccess the memory location containing the log file to read thetime-tagged data. If the parser resides on a remote computer, the parsercan communicate with the computer storing the log file, in order toaccess the time-tagged data.

[0029] The present invention is not limited to analyzing time-taggeddata stored in a log file. For example, in an alternative embodiment ofthe present invention, the parser can receive the time-tagged data inreal time from machines performing an industrial process. In such anembodiment, each unit of time tagged data, can be received, processed,and either stored for further analysis or discarded.

[0030] According to an important aspect of the invention, as the parserreads the time tagged data, the parser preferably applies one or morestate machines to the time-tagged data to identify events of interest.For example, in step ST2 of FIG. 2, the parser applies a first statemachine to one entry of the time-tagged data. The first state machinecan analyze the data to identify an event or events occurring in anindustrial process and produce output relating to the event or events.In step ST3, the parser determines whether all of the state machineshave been executed. If all of the state machines have been executed, theparser determines whether all of the time-tagged data has been analyzed(step ST4). If all of the data has been analyzed, the parser ends, andthe program computes statistical measures for the data produced by thestate machines (Step ST2 in FIG. 1).

[0031] In step ST3 of FIG. 2, if all of the state machines have not beenexecuted, the parser preferably applies the next state machine to thecurrent time-tagged data entry (Steps ST4 and ST2). Thus, according toone embodiment of the invention, a series of state machines are appliedto each time-tagged data entry before proceeding to the next time-taggeddata entry. In an alternative embodiment of the present invention, eachstate machine can be applied to all of the time-tagged data receivedand/or stored in a log file before applying the next state machine.However, this embodiment is less desirable than applying all statemachines to each entry before proceeding to the next entry because somestate machines require data produced by other state machines. Thedifficulty in communicating data among state machines is increased whenstate machines are applied in full before applying subsequent statemachines. Once all of the state machines have been applied to all of thedata, control returns to step ST2 in FIG. 1 where statistical measuresare computed for the output produced by application of the statemachines to the time-tagged data.

[0032]FIG. 3 illustrates an exemplary state machine that can be appliedto time-tagged data in order to measure the time between starting andending events associated with an industrial process. For example, inpaper processing, the starting event can be the activation of a vacuumsolenoid of a sheet feeder. The ending event can be the detection of oneor both edges of a sheet of paper by a sensor, such as a mechanicalsensor, an optical sensor, a magnetic sensor, or an electrical sensor,associated with the sheet feeder. The following event list illustrates,without limitation, the exemplary events that can be monitored by thestate machine illustrated in FIG. 3:

Event List

[0033] A) Vacuum solenoid activated

[0034] B) System error detected

[0035] C) Motor power disabled

[0036] D) Lead edge of paper detected at photocell

[0037] E) Finished making output.

[0038] In the event list, events A and D are the starting and endingevents for which elapsed time can be measured. Events B, C, and E areother events that can cause transitions between states.

[0039] The state machine illustrated in FIG. 3 includes a plurality ofstates associated with the industrial process being monitored. In theillustrated embodiment, the states are:

[0040] S1: Waiting for Starting Event;

[0041] S2: Waiting for Ending Event; and

[0042] S3: Generating Output.

[0043] The arrows between the states in the state diagram representstate transitions. The events or state machine inputs that cause thetransitions are indicated by letters A-E beside each arrow. Theoperation of the parser in applying the state machine to a log filecontaining multiple entries of time-tagged data will next be explainedin detail.

[0044] In state S1, the state machine “waits” for a starting event tooccur. Waiting for a starting event to occur can include analyzing logfile entries until a log file entry corresponding to the event or eventsof interest is located. As discussed above with respect to FIG. 2, theparser can apply multiple state machines to each log file entry beforeproceeding to the next log file entry. Thus, for state Si of the statemachine illustrated in FIG. 3, the parser determines whether the currentlog file entry corresponds to event A, “Vacuum solenoid activated”. Inorder to determine whether the current log file entry indicates theevent of interest, the parser can apply a pattern matching algorithm tothe event portion of the entry. The pattern matching algorithm can beany suitable algorithm for matching the text string or code in the eventportion of the entry with a known text string or code corresponding tothe event of interest. For example, the pattern matching algorithm canbe similar to or the same as pattern matching algorithms used inInternet search engines or search programs of the Unix operating system.

[0045] An example of a time-tagged data entry that identifies thestarting event or activation of a solenoid is as follows:

EVENT A: Solenoid Activation 0002.752235 00.000274 00.095429SFVACSOL-BIN_OUT CLR: board=0,port=11,pin=000

[0046] As indicated by the data entry, the real-world eventcorresponding to the entry might not be readily identifiable to a humanobserver without knowledge of the meaning of text strings associatedwith real-world events. The parser reduces the need for users to befamiliar with log file data formats by automatically identifying eventsof interest from the time-tagged data units.

[0047] In the illustrated embodiment, if the parser determines that theevent portion of the entry corresponds to event A, “Vacuum solenoidactivated”, the state machine transitions to state S2 “Waiting forEnding Event”. If the parser determines that the current log file entrybeing analyzed does not correspond to event A, then the state machineremains in state S1. Thus, the state machine automatically filters outirrelevant events, such as events from other sensors or other machines,by only changing states when the event or events of interest occur.

[0048] Once the state machine transitions to state S2 and any remainingstate machines have been applied to the current entry, the parserexamines the next data entry for events relevant to state S2. In theillustrated embodiment, the parser determines whether the event portionof the next data entry corresponds to event B, “System error detected”,event C, “Motor power disabled, or event D “Lead edge of paper detectedat photocell”. If the parser determines that the event portion of thetime-tagged data entry corresponds to event D, the state machinetransitions to state S3.

[0049] The following is an exemplary time-tagged data entrycorresponding to the detection of a sheet of paper at the solenoid:

EVENT D: Sheet Detected 0002.784431 00.004516 00.035156SFENTCEL-BIN_MUX_IN SET: board=0,port=06,pin=000

[0050] In a complex industrial process, such as paper processing, manyevents can occur between the activation of a solenoid and the detectionof a first sheet of paper at the solenoid. For example, other solenoidscan be activated and paper can be detected by other sensors. These othernon-relevant events result in separation between the entriescorresponding to events A an D in FIG. 3. As a result, a human analyzingthe time-tagged data would be required to expend much time and effortsearching the log file for events A and D. However, because the parseraccording to the present embodiment implements one or more statemachines that automatically identify entries and sequences of entriescorresponding to events of interest, the time required for analyzingtime-tagged data is reduced, even when entries are interspersed withother non-relevant entries.

[0051] While in state S2, if the parser determines that the currententry corresponds to event B, “System error detected” or event C, “Motorpower disabled”, the state machine returns to state S1. The followingentries correspond to events B and C:

EVENT B: System Error Detected 0007.335153 00.002685 04.211392BASE-Error SET: SET Error=0x8251 EVENT C: Motor Power Disabled0040.408212 00.000274 23.874536 SFMOTPWR-BIN_OUT CLR:board=0,port=12,pin=000

[0052] Thus, in state S2, the parser is required to check the currententry for multiple events. If the state machine returns to state S1, theparser checks the next data entry for event A, as described above.

[0053] In state S3, the state machine generates output corresponding tothe parameter being measured. In the present example, the parameter isthe time from the activation of a vacuum solenoid to the presence of asheet of paper at the solenoid. The state machine can calculate the timeby subtracting the time tag of the entry that caused the transition tostate S2 from the time tag of the entry that caused the transition tostate S4. The state machine can output the time, e.g., in milliseconds,and a text string or code indicating that the time represents solenoidactivation to detection of paper. After generating the output, the statemachine returns to state S1 to wait for the next starting event.

[0054] As stated above, the parser preferably executes a plurality ofstate machines for analyzing time-tagged data to identify multipleevents and measure multiple parameters associated with the industrialprocess. FIG. 4 illustrates another state machine that can be executedby the parser according to an embodiment of the present invention. Thestate machine illustrated in FIG. 4 detects overlapped sheets of paperin the entry area of a turnover sequencer.

[0055] The following event list includes events that result in statetransitions in the state machine illustrated in FIG. 4:

Event List

[0056] A) Inside page lead edge detected;

[0057] B) Outside page lead edge detected;

[0058] C) Inside turnover lead edge detected; and

[0059] D) Outside turnover lead edge detected.

[0060] In a turnover sequencer (“TOS”), sheets of paper enterside-by-side and exit in an single overlapped stream. Thus, in the eventlist, event A corresponds to the detection of the leading edge of theinside sheet and event B corresponds to the detection of the leadingedge of the outside sheet. Event C corresponds to the detection of thelead edge of the inside sheet at the entry portion of the turnover areaof the turnover sequencer. Event D corresponds to the detection of theleading edge of the outside sheet at the entry portion of the turnoverarea of the turnover sequencer. Overlapped sheets are identified whenlead edges of the outside and inside pages are detected by the entryphotocells of the TOS before either enters the turnover area.

[0061] In state S1, “Waiting for Paper”, the parser determines whetherthe current log file entry corresponds to event A, “Inside page leadedge detected” or event B, “Outside page lead edge detected”. Exemplarylog file entries corresponding to events A and B are as follows:

EVENT A: Inside Page Lead Edge Detected 0010.02588000.00156000.324750RTENICEL-BIN_MUX_IN SET:board=1,port=06,pin=001 EVENT B: Outside LeadEdge Detected 0009.995850 00.00093000.125760 RTENOCEL-BIN_MUX_INSET:board=1,port=06,pin=001

[0062] In state S1, if event A occurs, the state machine transitions tostate B, “Inside Page Seen”. The parser preferably also executes anyremaining state machines relevant to the current log file entry. Theparser then reads the next log file entry and applies conditionsrelevant to state S2. In state S2, the parser determines whether thecurrent log file entry corresponds to event B or event C, “Insideturnover lead edge detected”. An exemplary time-tagged data entrycorresponding to event C is as follows:

Event C: Inside Turnover Lead Edge Detected 0011.705250 00.00297000.097980 RTTUICEL-BIN_MUX_IN SET:board=1,port=09,pin=001

[0063] If event C is detected, the state machine returns to state S1. Ifevent B occurs when the parser is in state S2, the state machinetransitions to state S3, “Two pages in Turnover Area”.

[0064] In state S3, the parser generates output indicating that twopages have entered the turnover area. When the parser has completedgenerating the output, the state machine automatically returns to stateS1 to wait for the next sheet of paper. When analyzing a log file,waiting for the next sheet of paper can include searching throughremaining log file entries until another entry corresponding to event Aor B is located.

[0065] When the state machine is in state S1 and event B is detected forthe current log file entry, the state machine enters state S4, “OutsidePage Seen”. In state S4, the parser analyzes the current log file entryto determine the presence of text indicating event A or event D,“Outside turnover lead edge detected”. An example of a log file entrycorresponding to event D is as follows:

EVENT D: Outside Turnover Lead Edge Detected0011.82426000.01203000.278430 RTTUOCEL-BIN_MUX_INSET:board=1,port=09,pin=001

[0066] In state S4, if the current entry corresponds to event A, theparser enters state S3, generates the output indicating the presence oftwo overlapped pages, and returns to state S1. If the current entrycorresponds to event D, the parser returns to state S1.

[0067] The state diagram illustrated in FIG. 4 illustrates that eventsresult in different transitions, depending on the current state. Interms of log file entries, this means that a given log file entry canhave a different meaning, depending on previous log file entries. Ahuman observer scanning a log file would be required to rememberprevious log file entries to determine the significance of current logfile entries. By applying state machines to each log file entry, theparser according to the present embodiment “remembers” previousinformation in order to determine the significance of presentinformation. Accordingly, the burden on the user in interpreting logfile data is significantly reduced. This advantage applies equally totime-tagged data that is recovered and processed in real time.

[0068] The methods and systems for analyzing time-tagged data are notlimited to applying the state machines in FIGS. 3 and 4 to time-taggeddata. These state machines are merely intended to illustrate, withoutlimitation, examples of how state machines can be applied to identifyreal-world events and measure parameters from time-tagged data. Anysuitable state machines that identify real world parameters or eventsfrom time-tagged data are within the scope of the present invention.

[0069]FIG. 5 illustrates an exemplary paper processing system in whichthe present invention can be used to analyze time-tagged data. Thesystem includes a cutter 100, a hold area 102, a TOS 104, an accumulator106, and a collector 110. The operation of each of these devices andexamples of how state machines can be applied to analyze time-taggeddata output from each of the devices will now be explained.

[0070] In the illustrated system, cutter 100 cuts pages at selectedlocations, e.g., at the boundaries of every page, slits pages that areprinted in 2-up applications, and removes any trim (i.e., tractor pinholes along the edges of a page). State machines can be applied totime-tagged data collected from this device to:

[0071] 1) Monitor the rate, e.g., in cuts per hour, at which cuts areperformed; and

[0072] 2) Monitor the delay, e.g., in milliseconds, between startingeach cut and when read data is available.

[0073] Hold area 102 holds pages after the pages are cut and before thepages enter other parts of the system. Hold area 102 is used to adjustthe timing relationship between two pages that are side-by-side in thecase of a 2-up application. State machines can be applied to time-taggeddata output from this device to:

[0074] 1) Monitor the speed e.g., in inches per second, at which paperenters hold area 102;

[0075] 2) Monitor the speed, e.g., in inches per second, at which paperleaves hold area 102;

[0076] 3) Monitor the amount of time, e.g., in milliseconds, that pagesstay in hold area 102;

[0077] 4) Measure paper skew, e.g., in milliseconds, at entry to holdarea 102; and

[0078] 5) Measure difference, e.g., in milliseconds, between left andright pages leaving hold area 102 for 2-up applications.

[0079] TOS 104 moves two pages through a right-angle turn, convertingthe pages from two side by side streams to a single stream in which thepages may or may not overlap. Pages that move through a TOS are flippedover in the turnover process. State machines can be applied totime-tagged data output from this device to:

[0080] 1) Monitor the speed, e.g., in inches per second, at which paperenters TOS 104;

[0081] 2) Measure difference, e.g., in inches, between left and rightpages entering TOS 104 for 2-up applications;

[0082] 3) Detect single and overlapped pages and report to other statemachines via flares, which are discussed in more detail below;

[0083] 4) Measure the amount of overlap, e.g., in inches, at varioussensors and monitor how the amount of overlap varies as a page movesthrough the rest of the machine;

[0084] 5) Monitor the speed, e.g., in inches per second, at which paperleaves TOS 104; and

[0085] 6) Monitor the paper speed, e.g., in inches per second, atsensors internal to TOS 104.

[0086] Accumulator 106 combines and stacks single and overlapped pagesinto multiple-page sets. Set sizes range from one page up to the maximumallowed by the mechanical limits of folder 108. Each set will beinserted into one envelope, possibly with other sets destined for thesame customer. State machines can be applied to data output from thisdevice to:

[0087] 1 ) Monitor the speed, e.g., in inches per second, at which paperenters accumulator 106;

[0088] 2) Monitor the speed, e.g., in inches per second, at which paperleaves accumulator 106;

[0089] 3) Monitor the amount of time, e.g., in milliseconds, that pagesstay in the area of accumulator 106;

[0090] 4) Count the number of pages in each set and report to otherstate machines via flares;

[0091] 5) Monitor time delay, e.g., in milliseconds, between releasingof a brake and detection of paper at the exit of accumulator 106; and

[0092] 6) Monitor and compare times for pages in the upper deck ofaccumulator 106 versus the lower deck of accumulator 106.

[0093] Folder 108 folds sets in a predetermined pattern. State machinescan be applied to time-tagged data output from this device to:

[0094] 1) Monitor the speed, e.g., in inches per second, at which paperenters folder 108;

[0095] 2) Monitor the speed, e.g., in inches per second, at which paperleaves folder 108;

[0096] 3) Monitor differences in speed, e.g., in inches per second, fordifferent set sizes; and

[0097] 4) Monitor differences in speed, e.g., in inches per second, forsets from upper vs. lower decks of accumulator 106.

[0098] Collector 110 provides an area where folded sets can be combined(or collected) with other folded sets destined for the same customer,which is known as sub-set collection. State machines can be applied totime-tagged data output from this device to:

[0099] 1) Monitor the speed, e.g., in inches per second, at which paperenters collector 110;

[0100] 2) Monitor set distributions, e.g., in pages per set;

[0101] 3) Monitor behavior differences between sets from upper and lowerdecks of accumulator 106; and

[0102] 4) Monitor speed differences for heavy vs. light sets.

[0103] Another function of collector 110 is to provide a two-stageholding area to allow one area of an inserter (not shown) to synchronizesets passed to the next area of the inserter. This small buffer areadecouples operation of these two machine parts and allows productivityto be maintained when large and small sets are mixed. State machines canbe applied to time-tagged data relating to set synchronization outputfrom this device to:

[0104] 1) Monitor the speed, e.g., in inches per second, at which paperleaves collector 110;

[0105] 2) Monitor speed differences, e.g., in inches per second, forheavy vs. light sets; and

[0106] 3) Monitor the rate, e.g., in sets per hour, at which sets leavecollector 110.

[0107] Yet another function of collector 110 is to provide the abilityto divert (or remove) sets containing errors from the processing stream,such as to a divert area, without requiring operator intervention ormachine stoppage. State machines can be applied to time-tagged datarelating to this device function to:

[0108] 1) Monitor the speed, e.g., in inches per second, at whichdiverted sets move through the divert area;

[0109] 2) Count the number of diverted sets, e.g., in diverts per hour;and

[0110] 3) Identify patterns in reasons, such as bad read, cover opened,too many pages, for diverting sets.

[0111] The present invention is not limited to applying state machinesto time-tagged data from the paper processing machines illustrated inFIG. 5. For example, additional paper processing machines to which themethods and systems according to the present invention can be appliedinclude sheet feeders, bursters, readers, and other paper processingequipment. A sheet feeder is a paper processing device that provides astream of single sheets from a stack of cut sheets. A sheet feeder isused in place of a cutter or a burster when a customer decides to printindividual sheets instead of rolled or fan folded paper. State machinescan be applied to time-tagged data output from a sheet feeder to:

[0112] 1) Monitor the rate, e.g., in sheets per hour, at which sheetsare fed;

[0113] 2) Monitor the delay, e.g., in milliseconds, between startingeach page and when read data is available; and

[0114] 3) Monitor the delay, e.g., in milliseconds, between command tostart feeding and detection of paper movement.

[0115] As recognized by those of skill in the art, a burster is a paperprocessing device that provides a stream of single sheets from paperthat has been horizontally perforated at page boundaries. A burster canalso convert 2-up printing into a singulated stream of sheets and willremove any trim (i.e., tractor pin holes along the edges of page). Statemachines can be applied to time-tagged data output from a burster to:

[0116] 1) Monitor the rate, e.g., in sheets per hour, at which sheetsleave the burster;

[0117] 2) Monitor the gap, e.g., in milliseconds, between sheets; and

[0118] 3) Monitor the speed, e.g., in inches per second, at which sheetsleave the burster.

[0119] As stated above, the methods and systems for analyzingtime-tagged data according to the present invention can be used toanalyze time tagged data output from a reader. A reader is a paperprocessing device that provides an area where printing on the paperrepresenting processing instructions are obtained for each sheet thatenters the machine. The reader can be separate from or combined with aburster. A reader may also be combined with or separate from cutters andsheet feeders. State machines can be applied to time-tagged data outputfrom a reader to:

[0120] 1) Monitor the rate, e.g., in sheets per hour, at which sheetsenter the reader;

[0121] 2) Monitor the speed, e.g., in sheets per hour, at which sheetsenter the reader;

[0122] 3) Monitor the speed, e.g., in inches per second, at which sheetsleave the reader;

[0123] 4) Monitor the gap, e.g., in milliseconds, between sheets at theentry of the reader;

[0124] 5) Monitor the gap, e.g., in milliseconds, between sheets at exitof the reader; and

[0125] 6) Monitor the number or count of sheets in the reader at anytime.

[0126] From the above-listed devices it is apparent that in paperprocessing, a plurality of machines act in concert in performing aspecified function, such as stuffing an envelope. This results in largequantities of time-tagged data entries that are interspersed with eachother. Manually analyzing such data is impractical for untrainedpersonnel and time consuming for personnel trained to analyze such data.However, because the methods and systems for analyzing time-tagged dataapply localized state machines to the time-tagged data, real-worldevents and parameters associated with each device can be easilyidentified.

[0127] In the examples described above, parameters are measured ininches per second and milliseconds. However, the present invention isnot limited to measuring parameters in milliseconds or inches persecond. For example, other units for which parameters can be calculatedinclude inches, mils ({fraction (1/1000)} of an inch), cycles per hour,and percentages, e.g., percentages of data points falling within aspecified value range.

[0128] The present invention is not limited to methods and systems foranalyzing time-tagged data for the devices described above. For example,additional devices for which the methods and systems according to thepresent invention may be used to analyze time-tagged data includesorters and inspection devices. Analyzing time-tagged data from any mailor paper device is within the scope of the invention.

Flares

[0129] According to an important aspect of the invention, state machinespreferably share data with other state machines. More particularly, whenone aid state machine produces data needed by another state machine, thefirst state machine preferably communicates the data to the second statemachine. This inter-state-machine communication is referred to herein asa “flare”.

[0130] For example, suppose state machine A executes and detects theoccurrence of an event relevant to the execution of state machine B.Rather than re-executing the steps required for detecting the occurrenceof the event, state machine B preferably uses the event produced bystate machine A. In order to communicate the occurrence of the event tostate machine B, state machine A can write data indicating theoccurrence of the event in a memory location accessible by the processexecuting state machine B. The process executing state machine B canread the memory location containing the data. As a result, the stepsrequired for detecting the occurrence of the event are preferablyexecuted only once.

[0131] In addition to communicating data indicating the occurrence of anevent between state machines, the parser can also communicate the timeof occurrence of the event between state machines. However,communicating the time of occurrence of an event is not a requiredfeature of the invention. For example, if the event detected by statemachine A is “A man walked through the door” or “A woman walked throughthe door”, this data can be communicated to state machine B withoutcommunicating the time of the event to state machine B. Alternatively,state machine A could communicate the time that the man or woman walkedthrough the door to state machine B. However, if it is desirable toreport a time along with the occurrence of an event, it is alsopreferable that the time be defined with regard to the event. Forexample, in the example discussed above, the time that the man or womanentered the door or completed walking through the door can be reported.Any suitable method of defining and communicating time between statemachines is within the scope of the invention.

[0132] Using flares to communicate the occurrence of events betweenstate machines greatly reduces software complexity as will be readilyappreciated by those of skill in the art. As a result, programsimplementing the state machines might execute more quickly. Flares alsoaid in the overall design of the parser. For instance, in paperprocessing, if a single state machine is designed to monitor an area ofthe machine where more than one page could pass through before thatstate machine produces its output (or not) for the first page, thecomplexity of the overall design of the parser can be increased. Flaresallow the localization of state machine operation to a small area of adevice, such as the turnover area of a TOS and/or related processingequipment. This localization greatly simplifies the design of each statemachine that needs to span several machine areas to produce a certainoutput. Thus, flares can be used to provide an indication of an eventwhich occurred elsewhere in the machine being maintained to modify thebehavior of a state machine that relates to processes further downstreamin the system being monitored.

[0133] One example in which flares can be useful in a paper processingenvironment specifically is to communicate the presence of overlappedpages in a Turnover Sequencer (TOS). In paper processing, the TOSchanges paper motion at the exit into one at right angles to papermotion at the entry. This change in paper motion results in a rightangle turn. The TOS is constructed to simultaneously receive two pagesside-by-side (2-up) and turn them over so that the pages exit the devicein a single stream. The page on the outside of the turn takes longer topass through the TOS and therefore experiences a natural delay becauseit has to travel slightly farther than the inside page. This action“sequences” the pages so that the page that will come out first can beidentified. This action also overlaps the pages so that two pages cantravel through the paper processing machines in the same space toimprove productivity. When overlapping pages in this manner, it isundesirable for the pages to pull apart, because the order in which thepages will overlap at the next stage in the paper processing sequencemight not be easily determinable. Therefore, it is desirable to monitorthe amount of overlap for such page groups while ignoring single pages(which are not overlapped) that pass through the TOS.

[0134] A TOS can include four photocells over which overlapped andsingle sheets pass. Each of the photocells can be used to measure theamount of overlap. Overlap detection is preferably started at the entryto the TOS when pages are still side-by-side. This is the principle onwhich the state diagram illustrated in FIG. 4 is based. From the designof the TOS, i.e., the length between the entry photocells and theturnover area, if two lead edges cross their respective entry photocellsbefore either enters the turnover area, the pages will overlap. It mightnot be known which of the sheets will enter the turnover area first, asthis depends on the specific shape of the paper being processed.However, if both sheets are present in the turnover area without anexit, it can be assumed that an overlapped set coming is travelingthrough the TOS.

[0135] The state machine illustrated in FIG. 4 can be used to detect thepresence of overlapped pages. For example, the state machine can monitorthe entry photocells of the TOS for lead edges. The state machine isstructured so that either sheet, i.e., the inside sheet or the outsidesheet, can enter the TOS first. For example, Events A and B in FIG. 4are parallel paths to states S4 and S2, depending on whether the insidepage or the outside page is detected first. In state S2 or state S4, onepage has detected. If another page is detected at the TOS entry, thestate machine transitions to state S4, which indicates that two pagesare in the turnover area. In state S4, it can be assumed that the pagesthat entered the TOS are overlapped.

[0136] Because the detection of overlapped pages is an important eventthat can be used by downstream devices, the state machine illustrated inFIG. 4 preferably sends a flare to all other state machines. The flarepreferably includes a unique name. Another state machine, for example,the state machine analyzing the data collected by the first overlap cellcan be watching for that name. When the state machine analyzing datacollected by the first overlap cell receives the flare, it classifiesthe page as an overlapped set and reports it as such. If the flare isnot received, the state machine analyzing data collected by the firstoverlap cell assumes that the page currently detected by the statemachine is only a single page. Once the state machine analyzing datacollected by the first overlap cell then detects a page, the statemachine waits until the trail edge of the overlapped pages is detectedand “throws” another flare with a unique name that indicates anoverlapped page is leaving the first turn in the TOS. That flare is“caught by” a state machine that monitors the next photocell downstreamand treats the detection of pages overlapped pages. This process isrepeated for all state machines for which overlapped pages are relevant.

[0137] In paper processing, a key observation to remember is that papermight (or might not) simultaneously exist under many of thesephotocells. Any combination of pages could be overlapped at any time.The flares indicate when a page is overlapped and the unique name ofeach flare allows the state machines to keep track of multiple sets ofoverlapped pages. If a flare is thrown and a state machine does notrequire the information provided by the flare, the flare is ignored.

[0138] In addition to communicating information to downstream statemachines that can be discovered by upstream state machines, such as thepresence of overlapping pages, flares also pass information todownstream state machines that the downstream state machines are unableto discover without flares. For example, flares can be used to passpaper attributes, such as the number of pages in a set, previous pathtaken by the set, or processing applied to the set, along with the paperto which the attributes apply.

[0139] For purposes of tracking overlapped pages, it can be necessary toknow both the average time for a single page to pass a photocell, aswell as the time for each overlapped page to pass the photocell. Withflares, these two modes e of operation can be identified and trackedseparately. In a preferred embodiment of the present invention, aMicrosoft EXCEL® spreadsheet performs the calculations necessary todetermine the amount of overlap e.g., in inches or centimeters, for eachpage that is seen. If the average overlaps at each of the photocells ofinterest in the TOS are analyzed, it is apparent that the averageoverlap decreases at each successive stage in the TOS. This is an effectof how the machine runs and is expected. If paper processing begins withan overlap that is too small, the pages will separate and causesequencing problems. If the range of these values (max-min) is large,this can indicate errors in paper motion control software and otherproblems, such as insufficient drive pressure on paper. If the gapbetween lead edges varies at the start of the process, the amount ofoverlap variation increases as the pages proceed through the paperprocessing system. This variation in overlap has been observedexperimentally and utilized to modify paper processing control software.An analysis tool, such as a system for analyzing time-tagged dataaccording to the present invention, could have been used to detect thisissue before releasing the paper processing control software. Thus, themethods and systems for analyzing time-tagged data according to theinvention are useful in validating paper processing control software.

Statistical Analysis. Application of Design Limits, and OutputGeneration

[0140] Referring back to FIGS. 1 and 2, after the state machines areapplied to the time-tagged data, statistical measures are computed forthe output produced by the state machines, design limits are applied tothe statistical measures, and the output is displayed to a user.Exemplary statistical measures that can be computed for the data outputfrom the state machines include minimum values, maximum values, rangevalues, mean values, median values, standard deviation values, modevalues and variance values. For example, it can be desirable to know thespeed at which paper passes a given sensor in paper processing. In orderto determine the speed, it is necessary to know the page length anddetermine the amount of time for each page to pass by a photocell in themachine being monitored. The page length can be entered by the operatoror extracted from the time-tagged data. In order to avoid operatorerrors in entering the page length, it is preferable that the pagelength be included in the time-tagged data being tested. The amount oftime for a page to pass the sensor is measured by a state machine thatfinds the lead edge of the page, records the start time for thedetection of the lead edge, finds the trail edge of the same page, andrecords an end time for the detection of the trail edge. The transittime is calculated by subtracting the start time from the end time. Thestate machine produces a vector of numbers for a given batch of papersbeing processed indicating the transit times for a given photocell.

[0141] The final item required to be considered in computing speed isthe length of sensitive area under the photocell. Photocells do not havean infinitesimally small point where page edges are detected. Photocellshave a “hot spot” where a page anywhere in that area will be detected.For photocells commonly used in paper processing, this area is typicallyabout 0.2 inches for each cell, when measured empirically. The hot spotfor each photocell increases the apparent page length by the length ofthe hot spot. Thus, when computing the speed, the length of the hot spotis added to each page length. This value is then divided by the transittime for a page. The quotient is the speed in inches per second, orother appropriate unit, for each page. The speed values for the pagesbeing processed are stored as a vector of numbers, e.g., in aspreadsheet. From this vector, statistical measures, such as minimum,maximum, average, and standard deviation are calculated. This data canalso be used to generate graphs, such as histograms, indicating trendsin machine parameters.

[0142]FIG. 6(a) is an example of output that is generated fromtime-tagged data according to an embodiment of the present invention.The output comprises a graphical interface displayable on a computerdisplay device that allows the user to view data in various formats. Forexample, in FIG. 6(a), a first window 600 displays a plurality ofprocess parameter descriptions, such as “sheet feeder entry cell transittime”, that indicate parameter values of interest calculated fromtime-tagged data. Window 600 also includes status indicators thatindicate whether the parameters are within, near, or outside of designtolerances. In the illustrated embodiment, text messages, “OK”, “Warn”,and “Error”, are combined with familiar colors, green, yellow, and red,to indicate to the user whether a process is operating within designlimits. If a parameter is well within design limits, “OK” is displayedin a green box. If a parameter is close to, e.g., the average is withinthree standard deviations, of a design limit, “Warn” is displayed in ayellow box. If a parameter is outside of design limits, “Error” isdisplayed in a red box.

[0143] As an example of how design limits can be applied to statisticalmeasures, a design specification for an area can require that papershould run at 120 IPS, +/−5%. This results in-a lower and upper limit of114 IPS and 126 IPS, respectively. When time-tagged data is analyzed forthe machine, it can be determined that paper actually runs at an averageof 122.2 IPS with upper and lower measured values of 116 IPS and 123 IPSand a standard deviation of 1.5. Since both the upper and lower measuredvalues are within the design limits, a RED error message is notdisplayed. Warnings are then checked. A warning can be produced if theaverage is within +/−3 standard deviations of a limit. In this examplethe average of 122.2 plus three standard deviations is 126.7 (above theupper limit), so a warning can be indicated to the user. The averageminus three standard deviations is 117.7, which is not below the lowerlimit, so no warning is produced for the lower design limit.

[0144] The present invention is not limited to using text and colors toinform the user of the status of a particular process parameter. Anysuitable method can be used to communicate the status to a user inaccordance with this invention. For example, in an alternativeembodiment of the invention, an audible alarm can be used to indicatethat a process parameter is outside of an acceptable range.

[0145] When the user selects one of the parameter descriptions in window600, statistical information is displayed for that parameter descriptionin window 602 and a histogram is displayed for that parameter in window604. In the illustrated embodiment, “Sheet Feeder entry cell transittime” is selected in window 600. Accordingly, window 602 displaysstatistical data computed from measured and reference sheet feeder entrycell transit time data. Minimum, maximum, average, standard deviation,and count values are displayed in inches per second. Window 602 alsoincludes a dimensions button 606 and a print report button 608 thatallow the user to specify dimensions of paper or envelopes beingprocessed and print a report of the statistical calculations for all ofthe parameters displayed in window 600.

[0146] In addition to displaying measured data in the window 604,reference data is also displayed in the window 604. The reference datacan be measured data from previous paper processing operations.Simultaneously displaying the data produced from analyzing thetime-tagged data with the reference data greatly facilitatesinterpretation of the time-tagged data. The user can visually determinethe difference between the measured data and the reference data simplyby viewing the graphs in the window 604. As a result, the time and laborrequired to identify processing problems from time-tagged data isreduced.

[0147] In addition to displaying statistical data for measured values inthe window 604, reference data is preferably also displayed in thewindow 602. For example, in the illustrated embodiment, referencestatistical values are displayed for each measured statistical value.Displaying reference statistical values in the window 604 furtherfacilitates user interpretation of time-tagged data.

[0148] When the user selects dimensions button 606, a dimensions dialogbox, generally designated DDB, appears and allows the user to enterinformation that is not present in the time-tagged data, such as paperor envelope dimensions, dimensions of paper of envelopes beingprocessed. An example of dimensions dialog box DDB is illustrated inFIG. 6(b). Dimensions dialog box DDB illustrated in FIG. 6(b) permitsthe user to enter the following dimensions:

[0149] 1) page length;

[0150] 2) folded page length;

[0151] 3) envelope width; and

[0152] 4) envelope height;

[0153] for both reference and measured data. This allows the user tocompare operation of the machine when running jobs with different sizesof paper. The output line of each state machine has an embedded stringthat determines the proper units of measurement for class of data alongwith any design limits to use.

[0154] Because calculation of transit speed, e.g., in inches per second,depends on page or envelope dimensions. when the user changes the pageor envelope dimensions using dimensions dialog box DDB illustrated inFIG. 6(b), the calculated transit speed changes. The specifieddimensions should match those for the process for which the time-taggeddata was collected.

[0155] Otherwise, speed data can be incorrect and lead to falsemeasurements. In order to avoid this potential problem, as stated above,the page dimensions can be included in the time-tagged data. In anembodiment in which dimensions are included in the time-tagged data, thedimensions dialog box DDB may be omitted.

[0156] Referring back to FIG. 6(a), when the user presses print reportbutton 608, a process information dialog box appears for receivinginformation regarding the operator, machine, and additional information.FIG. 6(c) illustrates an example of a process information dialog box,generally designated PIDB, that can be displayed. In the illustratedembodiment, process information dialog box PIDB includes an input cellfor “Operator Name” to allow the operator to enter his or her name. Asecond input cell labeled “Machine ID” allows the user to enter theidentification number of the machine being tested. A third input celllabeled “Additional Info” allows the user to specify any additionalinformation, such as data relating to the test being run on a machine.Process information dialog box PIDB also allows the user to selectwhether to display the report on the screen before printing. Once theuser enters the process information dialog box illustrated in FIG. 6(c)and selects “Preview on Screen” the user clicks on “OK”. A report isdisplayed indicating calculated statistical values for each of theparameters displayed in the window 600.

[0157]FIG. 6(d) illustrates an example of a report that may bedisplayed. In the illustrated embodiment, the operator name, machineidentifier, and additional information entered into the processinformation dialog box illustrated in FIG. 6(c) are displayed on theupper portion of the report. In FIG. 6(d), the statistical measurescalculated from the time-tagged data are displayed in tabular format. Inthe column labeled “Item Description”, names of each of the parametersfrom the window 600 are displayed. The column labeled “Minimum” displaysminimum measured values for each of the parameters. The column labeled“Average” displays average values for each of the parameters. The columnlabeled “Maximum” displays maximum values for each of the parameters.The column labeled “Standard Deviation” displays standard deviationvalues for each of the parameters. Finally, the column labeled “Status”displays the status of each of the parameters, i.e., whether theparameter is within, near, or outside of design limits. A Warnings andErrors List is displayed to summarize parameters for which warnings orerrors were detected. The Warning and Errors list preferably alsoindicates the design limit that was exceeded, e.g., the minimum, themaximum, or average value for a parameter.

[0158] Referring back to FIG. 6(a), graph window 604 displays ahistogram of sheet feeder entry cell transit time. In the histogram, thehorizontal axis represents sheet feeder entry cell transit time ininches per second. The vertical axis represents the percentage of valuesfor each transit time. The bars represent sheet feeder entry celltransit times calculated based on time-tagged data, as discussed above.The lined portion of the graph represents reference values, which may bevalues extracted and calculated from time-tagged data for the samemachine at another time or from another machine.

[0159] The graphical interfaces for displaying the results of analyzingtime-tagged data can be contrasted with the raw time-tagged data entrieslisted above. Presenting statistical data indicative of real-worldevents and measurements in an industrial process greatly facilitatesinterpretation of the time-tagged data. The presentation of data inFIGS. 6(a)-6(d) allows the user to immediately determine whether amachine is operating within design limits, v while the raw time-taggeddata entries stored in the log file may require hours of manual analysisbefore such a determination can be made.

Methods and Systems for Analyzing Non-Time-Tagged Data

[0160] Although the embodiments of the invention described aboveillustrate methods and systems for analyzing time-tagged data, thepresent invention is not limited to such embodiments. For example, in analternative embodiment of the invention, data from any of the mail orpaper processing operations described above may be collected,statistically analyzed, and presented to a user in a manner thatfacilitates user interpretation of the data, for example, as illustratedin FIGS. 6(a) and 6(d). The data analyzed might or might not have timetags. For example, mail or paper processing control software may outputmeasured data, such as inches of paper passing a given sensor persecond. The paper processing control software may determine the paperspeed in inches per second based on knowledge of the length of eachsheet and the time required for sheets to pass a given sensor. Forexample, the length of each sheet may be input into the paper processingcontrol software and the time may be measured electronically. The lengthdivided by the time equals the speed.

[0161] In the case where the paper processing control software outputsspeed in inches per second, state machines would not be necessary tocalculate this data. Thus, referring back to FIG. 1, in the presentembodiment, parsing time-tagged data (step ST1) may be replaced by thesteps of locating log file entries containing measurements for a givenparameter or a given sensor and recording the measured values. StepsST2-ST4 would be the same as steps ST2-ST4 described above fortime-tagged data, whereby statistical measures are computed, compared toreference values, and displayed to a user. Thus, the methods and systemsfor analyzing time-tagged data according to the invention are equallyapplicable to analyzing non-time-tagged data associated with anindustrial process.

[0162] It is therefore seen that the present invention provides a novelautomated method and system for analyzing time-tagged data and, moregenerally, any data associated with an industrial process. As can beappreciated by those of skill in the art, it can also be seen that thepresent invention provides methods and systems for analyzing dataassociated with an industrial process to produce output that facilitatesinterpretation of the data.

[0163] It will be understood that various details of the invention canbe changed without departing from the scope of the invention.Furthermore, the foregoing description is for the purpose ofillustration only, and not for the purpose of limitation, as theinvention is defined by the following, appended claims.

What is claimed is:
 1. A method for analyzing time-tagged dataassociated with mail or paper processing comprising: (a) reading aplurality of time-tagged data items received from a plurality ofmachines associated with an industrial process, each data item includinga time-tag portion and an event portion, the time-tag portion indicatinga time of occurrence of an event associated with the industrial processand the event portion indicating the event; (b) parsing the time-taggeddata items to identify data items and produce output associated with anevent of interest; and (c) computing statistical measures from theoutput.
 2. The method of claim 1 wherein reading a plurality oftime-tagged data items includes accessing a log file containing thetime-tagged data items.
 3. The method of claim I comprising receiving aplurality of time-tagged data items in real time and wherein reading aplurality of time-tagged data items includes receiving the time-taggeddata items in real time.
 4. The method of claim 1, wherein parsing thetime-tagged data items includes applying at least one state machine tothe time-tagged data items for identifying time-tagged data itemsrelating to an event of interest and producing output relating to theevent of interest.
 5. The method of claim 1, wherein parsing thetime-tagged data items includes applying first and second state machinesto the time-tagged data items, the first state machine producing a firstoutput and communicating the first output to the second state machine,the second state machine producing a second output based on thetime-tagged data items and the first output from the first statemachine.
 6. The method of claim I further comprising comparing computedstatistical measures with reference values associated with theindustrial process and alerting the user when a predeterminedrelationship exists between the statistical measures and the referencevalues.
 7. The method of claim 1 further comprising simultaneouslydisplaying, on a computer display device, process parameter valuesdetermined from the time-tagged data and reference values for theprocess parameter values.
 8. A method for analyzing time-tagged dataassociated with mail or paper processing comprising: (a) reading aplurality of time-tagged data items received from a plurality ofmachines associated with an industrial process, each data item includinga time-tagged portion and an event portion, the time-tagged portionindicating a time of occurrence of an event associated with theindustrial process, the event portion indicating the event; (b) parsingthe time-tagged data items to identify data items and produce outputassociated with an event of interest, wherein parsing the time-taggeddata items includes applying first and second state machines to thetime-tagged data items, the first state machine producing a first outputand communicating the first output to the second state machine, thesecond state machine producing a second output based on the time-taggeddata items and the first output from the first state machine; and (c)computing statistical measures from the output produced by the secondstate machine.
 9. A method for identifying overlapped pages in anoverlap portion of a turnover sequencer in a paper processing system,the method comprising: (a) reading a plurality of time-tagged dataentries from a plurality of machines in a mail or paper processingsystem; (b) in a first state, applying a pattern matching algorithm toeach time-tagged data entry for identifying a lead edge of a sheet ofpaper at an inside entry photocell or an outside entry photocell of theturnover sequencer; (c) in response to detecting a sheet of paper at theinside entry photocell, transitioning to a second state for detecting asheet of paper at the outside entry photocell; and (d) in the secondstate, in response to detecting a sheet of paper at the outside entryphotocell, transitioning to a third state for producing outputindicating the presence of overlapped pages in the turnover area of theturnover sequencer.
 10. The method of claim 9 comprising: (e) in thefirst state, in response to detecting a sheet of paper at the outsideentry photocell, transitioning to a fourth state for detecting a sheetof paper at the inside entry photocell; and (f) in the fourth state, inresponse to detecting a sheet of paper at the inside entry photocell,transitioning to the third state for producing the output.
 11. Themethod of claim 9, comprising, in the third state, communicating theoutput from a first state machine monitoring data output from onesection of the turnover sequencer to a second state machine monitoringdata output from another section of the turnover sequencer.
 12. Themethod of claim 9, comprising, after producing the output, returning tothe first state.
 13. A method for identifying overlapped pages in anoverlap portion of a turnover sequencer in a paper processing system,the method comprising: (a) reading a plurality of time-tagged dataentries from a plurality of machines in a mail or paper processingsystem; (b) in a first state, applying a pattern matching algorithm toeach time-tagged data entry for identifying a lead edge of a sheet ofpaper at an inside entry photocell or an outside entry photocell of theturnover sequencer; (c) in response to detecting a sheet of paper at theinside entry photocell, transitioning to a second state for detecting asheet of paper at the outside entry photocell; (d) in the second state,in response to detecting a sheet of paper at the outside entryphotocell, transitioning to a third state for producing outputindicating the presence of overlap pages in the turnover area of theturnover sequencer; (e) in the first state, in response to detecting asheet of paper at the outside entry photocell, transitioning to a fourthstate for detecting a sheet of paper at the inside entry photocell; and(f) in the fourth state, in response to detecting a sheet of paper atthe inside entry photocell, transitioning to a third state for producingthe output.
 14. In a computer system having a graphical user interfaceincluding a display and a user input device, a method for displayingstatistical measures for selected parameter values produced fromanalysis of time-tagged data from a mail or paper processing system, themethod comprising: (a) displaying, on the display, a first windowincluding parameter descriptions for mail or paper processing parametervalues and status information indicating the results of comparing theparameter values to reference values; (b) displaying, on the display, asecond window including a table of statistical measures for a selectedparameter description in the first window; (c) displaying, on thedisplay, a third window including a graph of measured values for theselected parameter description; and (d) receiving input from a user forselecting the parameter description.
 15. The method of claim 14, whereinthe graph is a histogram of measured values for the selected parameterdescription.
 16. The method of claim 14 wherein the graph is a histogramof measured values and reference values for the selected parameterdescription.
 17. The method of claim 14 comprising receiving input fromthe user for printing a report including the statistical measures forthe selected parameter description.
 18. In a computer system having agraphical user interface including a display and a user input device, amethod for displaying statistical measures for selected parametersproduced from analysis of time-tagged data from a mail or paperprocessing system, the method comprising: (a) displaying, on thedisplay, a first window including parameter descriptions for mail orpaper processing values and status information indicating results ofcomparing the parameter values to reference values; (b) displaying, onthe display, a second window including a table a statistical measuresfor a selected parameter description in the first window; (c)displaying, on the display, a third window including a graph of measuredvalues for the selected parameter description; and (d) receiving inputfrom the user for selecting the parameter description, and in responseto receiving the input from the user, displaying, in the second window,a table of statistical measures for the selected parameter descriptionand displaying, in the third window, a graph of measured values for theselected parameter description.
 19. The method of claim 18 comprisingsimultaneously displaying, in the second window, reference statisticalvalues for the selected parameter description and statistical measuresfor the selected parameter description.
 20. A parser for analyzingtime-tagged data associated with mail or paper processing, the parsercomprising computer-executable instructions embodied in acomputer-readable medium for performing steps comprising: (a) readingdata items associated with an industrial process, the data items eachincluding a time tag portion indicating a time and an event portionindicating an event; and (b) applying at least one state machine to thedata items to produce output indicative of a mail or paper processingevent.
 21. The parser of claim 20 wherein applying the state machine tothe data items includes identifying starting events and ending eventsassociated with mail or paper processing events.
 22. The parser of claim21 wherein the starting events are detections of lead edges of sheets ofpaper passing a sensor in a paper processing system and the endingevents are detections of trail edges of the sheets of paper passing thesensor.
 23. The parser of claim 22 further comprising computing transittimes for the sheets of paper passing the sensor based on time tagsassociated with the starting and ending events.
 24. The parser of claim23 comprising computing transit speeds for the sheets of paper passingthe sensor based on the transit times, page lengths of the sheets ofpaper, and active area of the photocell.
 25. The parser of claim 20,wherein applying at least one state machine to the data items includesapplying an overlap detection state machine for detecting overlappedpages in a turnover sequencer of a paper processing system.
 26. Theparser of claim 25 including determining the amount of overlap for theoverlapped pages.
 27. A method for analyzing data associated with a mailor paper processing operation comprising: (a) reading data associatedwith the mail or paper processing operation to obtain parameter valuesfor a parameter or parameters of interest associated with the mail orpaper processing operation; (b) computing statistical measures for theparameter values; and (c) outputting the statistical measures in amanner that facilitates interpretation of the data.
 28. The method ofclaim 27 wherein reading data includes reading entries in a log fileassociated with the mail or paper processing operation and storingparameter values for the parameter of interest.
 29. The method of claim27 wherein reading data includes receiving parameter values in real timeand storing parameter values associated with a parameter of interest inreal time.
 30. The method of claim 27 wherein outputting the statisticalmeasures includes simultaneously displaying the statistical measures andreference values for the statistical measures on a computer displaydevice.
 31. The method of claim 27 wherein outputting the statisticalmeasures includes displaying, on a computer display device, a firstwindow including parameter descriptions and a second window fordisplaying statistical measures of parameter values for a selectedparameter description.
 32. The method of claim 27 comprising displayinga window including a graph for simultaneously displaying measuredparameter values and reference parameter values associated with the mailor paper processing operation.